1. Technical Field
The present invention relates to a liquid ejection apparatus, such as an inkjet recording apparatus, and a production method for a liquid ejection apparatus, and in particular, it relates to a liquid ejection apparatus equipped with a cap for sealing a nozzle forming face of a liquid ejection head, and a production method for such a liquid ejection apparatus.
2. Related Art
Examples of a liquid ejection head that allows liquid droplets to be ejected (discharged) through nozzles by causing pressure variations in liquids inside pressure chambers include, but are not limited to, an inkjet recording head (hereinafter referred to as just a recording head) for use in image recording apparatuses, such as an inkjet recording apparatus (hereinafter referred to as just a printer); a color material ejection head for use in manufacturing color filters for liquid crystal displays and the like; an electrode material ejection head for use in forming electrodes for electro luminescence displays, face emitting displays (FED), and the like; and a living organic material ejection head for use in manufacturing biotips (biochemical elements). Further, in the recording head for use in image recording apparatuses, inks in liquid form are ejected, and in the color material ejection heads for use in display manufacturing apparatuses, solutions for color materials in R (red), G (glean), and B (blue) colors are ejected. Further, in the electrode material ejection heads for use in electrode formation apparatuses, electrode materials in liquid form are ejected, and in the living organic material ejection heads for tip manufacturing apparatuses, solutions for living organic materials are ejected.
In the above printers, a cap for sealing a nozzle forming face of the recording head is provided in order to prevent solvents for inks from being vaporized through nozzles of the recording head, and to perform maintenance processing for forcibly discharging viscosity increased inks and air bubbles from the nozzles by supplying negative pressure to the nozzles. The cap is a tray-shaped member having elasticity and is configured to seal the nozzle forming face within a sealing space (a capping state) by bringing a head edge face (an opening periphery) of the cap into contact with a bottom face at which the nozzle forming face is disposed in the recording head. For example, in a printer disclosed in JP-A-2001-341318, a cap formed by integrally molding a cap portion made of a thermoplastic elastomer material having elasticity with a holder portion made of a relatively hard synthetic resin material by means of insert molding or two-color molding is employed.
In a configuration in which an elastomer material is used as a material of the cap, ink inside the cap is likely to creep up on portions on side walls of the cap, such as corner portions where adjacent side walls intersect with each other, because of a capillarity; reach a portion to be brought into contact with the bottom face of the recording head; and be adhered to the bottom face of the recording head during a capping operation. Further, there is a problem that, upon contact of the recording head with a recording medium, such as recording paper, the ink adhered on the bottom face of the recording head taints the recording medium. Further, among recording heads of recent years, a recording head configured to include a protruding face protruding from its nozzle forming face toward a side of a recording medium being subjected to printing, and to perform recording of images and/or the like in a state of allowing the protruding face to press the recording medium is proposed, but in such a configuration, when the ink is adhered on the protruding face, the ink is likely to taint the recording medium when the recording medium has been pressed by the protruding face. In order to prevent the above creep-up of the ink, a liquid repellent treatment on the cap is considered, but there is a problem that it is difficult to expect a durability performance enough to endure repeatedly executed capping operations.